I will provide some speculation, but first some back story, as I recall it: Max Headroom was, to start with, a collection of special effects to make a British talk-show host seemingly generated by computer, but still able to interact
live with guests, etc. (A little bit of the same niche which the early muppets occupied, actually. See the early appearances of Rowlf the Dog on American talk show TV, for instance.) Anyway, the effect proved so captivating and convincing that the show became hugely popular, and a TV Movie was made (still in England) which provided a sci-fi style origin story for the (ostensibly computer generated) Max Headroom character. The character’s popularity was still rising, also in the USA (Coca-Cola famously used Max Headroom for their campaign for the now infamous New Coke), so an American TV series was proposed and made, with most of the same cast reused in the same roles, and the story of the TV movie was used (IIRC) as the two first episodes, except for a slightly happier ending to set it up as an ongoing TV series.
The problem, I guess, was that probably none of the U.S. people greenlighting the TV series had actually watched the original British TV movie; they probably only thought about getting such a popular character. They probably did not know that things like 1984, Judge Dredd and V for Vendetta are all very distinctly British things. The Max Headroom TV movie, as well as the TV series, are both essentially very dark cyberpunk; acerbically critical of prevailing trends in technology and also scarily prescient for 1987. It was also very critical of television itself as a phenomenon, which was probably what ultimately killed it, and by that time the huge fad for the character had passed.